Author(s): Rui Aleixo; Sandra Soares-Frazao; Mustafa Altinakar; Yves Zech
Keywords: Dam-break; Initial stages; Water column; Gate effect; Image analysis
Abstract: In dam-break flow experiments, the instantaneous dam-break is usually modeled by a moving gate whose removal time has to be small enough to not disturb significantly the flow in the initial instants. The gate motion direction, up or downward, is also an important parameter that will affect the initial instants of the dam-break flow propagation. In this paper an analysis of the gate removal effect in the initial instants of the dam-break flow is made considering two different initial water heights. By analyzing the water column behavior immediately after the dam-break, a new criterion for downward moving gates is presented. Finally, the analysis of the gate opening by imaging methods allowed also for a time resolved analysis of the velocity field in the initial instants of the dam-break flow for the two tested conditions.